MediumBiologyHigh School (11–12)Diversity of Living Organisms › Classification of Living OrganismsDiversity of Living Organisms › AlgaeConceptualdata
Tara studies four plants that look almost the same.
Contributed by StemPy LabTry it on paper first. A hint, the key idea and the worked solution are here when you need them.
Tara studies four plants that look almost the same. She counts the chromosomes in their root tip cells.
| Plant | Chromosomes in each cell |
|---|---|
| A | |
| B | |
| C | |
| D |
- Which kind of taxonomy is she using?
- Which two plants are most likely the closest relatives?
- What do and suggest about B and D?
Need a reminder? The key ideaShow
Artificial systems used a few superficial characters, such as the number of stamens (Linnaeus), and gave vegetative and sexual characters equal weight. Natural systems (Bentham and Hooker) used many external and internal features. Phylogenetic systems follow evolution. Numerical taxonomy scores all characters with equal weight; cytotaxonomy uses chromosomes; chemotaxonomy uses chemicals.
The worked solution
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Step 1. The method. Chromosome number is evidence from the cell, so this is cytotaxonomy.
Step 2. Closest. A and C both have chromosomes, so they are most likely the closest relatives.
Step 3. B and D. and . B and D may have arisen from the same stock by doubling and tripling the chromosome sets. They are related, but they are now different.
Answer: Cytotaxonomy; A and C; B and D seem to have and times the basic set of .
Discussion (0)
Log in to join the discussion.
Loading…